Need help picking an APC

[Inquisitive Builder]

Just lost the more thorough thread I just wrote, so this new one will be brief lol.

I just installed an AC on the same circuit as my main PC, and I should be barely be able to run all my stuff without tripping the circuit breaker, but I want a good backup power supply just in case so I can have a minute to shut down my computer properly without data loss before I go out and reset the breaker.

I'd like to be able to power my slim PS3, one IPS LED monitor, and my PC which has this power supply
http://www.amazon.com/Corsair-Enthusiast-Certified-Compatible-platforms/dp/B004LB5AZY/ref=sr_1_1?ie=UTF8&qid=1392430024&sr=8-1&keywords=corsair+tx650
I don't need them to run very long, just a few minutes so I can shut down safely.

I would try to pick this myself, but most are measuring in VA instead of Amps and talking about sine waves and all sorts of things I'm not knowledgeable about.

On a side note, I'd also like and extension cord that I could plug the APC into, but would any orange cord do?

Thanks guys, any help will be appreciated

 

[Saberus]

I think 900VA would be plenty, but I could be wrong.

I would caution against an extension cord unless it's an absolute necessity. If it is a necessity, get something with a thick gauge to minimize possible issues, and only as long as you need.

 

[blazorthon]

APC is a company. The product you are talking about is called a UPS; an uninterruptible power supply. I am not an expert on these, but I can still help at least a little.

This will help you understand VA:
https://en.wikipedia.org/wiki/Volt-ampere

Basically, the more inductive or capacitive the load, the more current it takes despite real power draw not changing. You don't need to fully understand it and really, it shouldn't be a big deal for modern computers since nearly all power supplies have at least passive power factor correction (most these days are getting active, which is excellent) and this greatly reduces the effect of capacitance/inductance (inductance is what computers and most other appliances tend to deal with).

The output of most UPS units isn't quite like what you get from the wall, it is "dirty". The closer to a real sine wave it is, the better.

The curved line (black) is a sine wave, the squarish line (blue) is a square wave. The staircase line (red) is a stepped sine wave. A UPS- uninterruptible power supply- is a battery backup. Batteries are DC, not AC, unlike the power from the wall that the power supply is built to work with. So, the UPS needs to take the DC power and make it into a pseudo sine wave for the power supply to function. The closer to a sine wave (IE more curved), the better. Typically, you'll see stepped waves from UPS units.

That's the basics.

You can plug a computer and monitor into a UPS, granted some power supplies are better suited to it than others. I don't know if a PS3 is fine with a UPS or not. I wouldn't expect issues, but I make no guarantees. Not all electronics can handle the "dirtier" (dirtier meaning less like a proper sine wave) power associated with most UPS units.

I agree with Saberus, although I'd hold off on recommending how much power you need until you tell us the components in your computer. Also, do you know how much money you want to spend on this?

 

[thx1138v2]

I would think the APC site would have a calculator to use to help you determine which unit to select.

If you want to understand more:

The calculations can get complicated. Generally speaking, VA (Volt Amps) is AC equivalent of DC Watts. The power rating on the PSU will be DC output in Watts and you need to figure out what the input will be to attain that output. The specs on that PSU say it is 85% efficient so divide 650 by 0.85 and that will be the required nominal input for maximum output on that PSU, or 765 VA. There are other factors that come into play so round that up to 800 VA just to be safe.

Then you need the power requirements for the PS3 and the IPS monitor and add them to the 800 VA for the computer PSU to get the nominal size of the UPS. I would guess 1000 VA would be enough. More is always better than less.

Once you figure out the total VA needed divide the VA by your voltage (120V in the US) and that will give you the amperage your extension cord needs to handle. For our example that would be roughly 8 amps. Use the shortest extension cord possible and select the wire gauge of the cord to suit 8 amps. Generally speaking you can use the following table for amperage vs wire gauge.

Up to 15 amps - 14 AWG wire
15-20 amps - 12 AWG wire
20-30 amps - 10 AWG wire

So you should be able to use a 14 AWG extension cord with no problems if it isn't too long. For long extension cords go up in the wire size (lower AWG #). Again, larger wire is better. Larger wire has a smaller gauge #, 10 AWG is larger than 12 AWG which is larger than 14 AWG.

 

[Saberus]

If you can afford a unit with sine-wave output, it's good to go with that. Cyberpower makes affordable models and have a good reputation.

Not sure how Cyberpower creates their sine wave output, but one way I have seen is using PWM for positive and negative voltage into a transformer with a filter capacitor to smooth the pulses into an analog AC waveform.

You can see this here: https://www.youtube.com/watch?v=6yMNlU9gueU

 

[Inquisitive Builder]

Alright, thanks for the input guys, I feel more aware of what I'm looking for now
Found this helpful video and wanted to share https://www.youtube.com/watch?v=6ikkpOpdES0

Looks like I have narrowed it to two similar options

This cyberpower
http://www.amazon.com/gp/product/B00429N19M/ref=ox_sc_imb_mini_detail?ie=UTF8&psc=1&smid=ATVPDKIKX0DER
Which should have just enough wattage and the “pure sine” feature, but not a lot else. From 2010

Or this APC one that is selling for almost half off
http://www.amazon.com/APC-BR1500G-Back-UPS-10-outlet-Uninterruptible/dp/B002RCNX8K/ref=sr_1_1?&s=electronics&ie=UTF8&qid=1438876894&sr=1-1&keywords=APC+br1500g
It has a huge warranty on replacing equipment if it EVER fails, which is attractive. It also has a very appealing “powerchute” function that automatically saves and shuts down the PC, which seems very important if I left it downloading something and somehow didn’t notice the circuit blew out, but the more I think about it that would probably never happen. Also 1500 VA instead of 1350, which should give me more headroom. Biggest thing is NO PURE SINE. It is also from 2004, though I’m not sure if that matters as much with batteries.

There’s also this one from 2014 that I had considered
http://www.amazon.com/CyberPower-BRG1500AVRLCD-1500VA-Outlets-GENERATION/dp/B00LEFYISA/ref=sr_1_1?s=electronics&ie=UTF8&qid=1438877286&sr=1-1&keywords=cyberpower+brg1500avrlcd
But I’m pretty sure it falls behind the APC one with no redeeming qualities but its age.

Thoughts? Is year of original release an issue here? And which is more valuable, Pure Sine or a bigger warranty, powerchute, and 1500 VA?

Thanks guys

 

[blazorthon]

The year the model came out isn't very important. The age of the battery inside is important, but I doubt the battery you get will be that old.

As for your other question, that depends on what you want. A better sine wave would be safer for what you plug in. If you think you would get enough time from the 600VA that will probably power a 400ish Watt computer and monitor setup for about two minutes. The 1500VA model might get you like five to ten times as much time.